1. Field of the Application
The application relates in general to a battery gas-gauge circuit and a method thereof, and more particularly to a battery gas-gauge circuit and a method thereof for obtaining the battery power with high accuracy by recording the leakage current of the coupled battery.
2. Description of the Related Art
Nowadays, as the rapid development of scientific technology makes popular the electronic devices, not only the customer requests the function of electronic device, but every enterprise attempts to develop a thin and light electronic device so as to meet the expectations of customer who expects to carry it with convenience. The electronic device is, for example, a notebook. Instead of using a conventional separation way in which the notebook and the battery module are separately disposed, every enterprise uses, for example, an integration way of fixedly coupling a battery module to a notebook, so as to minimize the volume and weight of the notebook.
Integrating a conventional battery module which is separately disposed into the electronic device contributes to a reduced volume and weight. However, the battery module is not allowed to be replaced by the customer since it has fixedly coupled to the electronic device. As for the notebook integrated with the battery module, due to the coupling relationship between the battery module and electronic device, a leakage current may be generated even in such a situation that the notebook is not operated, thereby increasing power dissipation. Moreover, the leakage current is so weak, such as which is smaller than a current dead-band, that the battery module may regard it as noise and neglect it. So that, the customer doesn't understand how much real battery power the battery module have.
In this regard, if the battery module of the electronic device runs out of its battery power before being delivered to each business shop, such as being stored in a stockroom thereof, the customer who purchases this electronic device may find it gone, i.e. out of battery, and use an adaptor to recharge this electronic device. At this time, because the battery module corresponds to the status of having charged up as in its factory, the electronic device shows on its screen that the battery module is charged up. As a result, the customer may wonder for the thing that whether the electronic device or the battery module is defective product, and every enterprise will receive customer complaint frequently which influences business reputation seriously.